Note 3 - Details of Consolidated Balance Sheet Accounts - Prepaid Expenses and Other (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Insurance premiums	$ 2,356	$ 1,831
Contract with Customer, Asset, Net, Current, Total	1,729	1,823
Other	3,166	2,971
	20,938	19,924
License Fees Member [Member]
Prepaid expenses	5,321	4,760
Tires In Service [Member]
Prepaid expenses	4,972	5,011
Parts And Tires Inventory [Member]
Prepaid expenses	$ 3,394	$ 3,528

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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